.login-container{
    width: 100%;
    height: calc(100% - 50px);
    /* 需要让里面的子元素, 垂直水平居中, 需要用到 flex 布局 */
    display: flex;
    align-items: center;
    align-content: center;
    justify-content: center;
}

.login-dialog{
    width: 400px;
    height: 350px;
    background-color: rgba(255,255,255, 0.8);
    border-radius: 10px;
}

.login-dialog h3{
    text-align: center;
    padding: 50px 0;
}

.login-dialog .row{
    height: 50px;
    width: 100%;

    display: flex;
    align-items: center;
    justify-content: center;
}

.login-dialog .row span{
     /* 把 span 转成块级元素, 方便设置后续尺寸 */
    display: block;
    width: 100px;
    font-weight: 700;
}

#username, #password{
    width: 200px;
    height: 40px;
    font-size: 22px;
    line-height: 40px;
    padding-left: 10px;
    border-radius: 10px;
    /* 去边框 */
    border: none;
    /* 去轮廓 */
    outline: none;
}

.row button{
    width: 300px;
    height: 50px;
    border-radius: 10px;
    color: white;
    background-color: rgb(0, 128, 0);
    border: none;
    outline: none;

    margin-top: 50px;
}

.row button:active{
    background-color: #666;
}